Microchip and method of manufacturing microchip

ABSTRACT

Provided is a microchip including: an inlet part to which a liquid is injected; a plurality of analysis areas to which the liquid is supplied from the inlet part; and a flow channel which is formed to supply the liquid to the plurality of analysis areas at the same time.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Japanese Priority PatentApplication JP 2013-074628 filed Mar. 29, 2013, the entire contents ofwhich are incorporated herein by reference.

BACKGROUND

The present technology relates to a microchip and a method ofmanufacturing the microchip. More specifically, the present technologyrelates to a microchip provided with a flow channel which is formed tosupply a liquid to a plurality of analysis areas at the same time.

In recent years, a microchip has been developed in which fine processingtechnology is applied in the semiconductor industry and a well or a flowchannel is installed in a substrate made of silicon or glass to performchemical and biological analysis.

An analysis system using such a microchip is called a micro totalanalysis system (μ-TAS), lab-on-a-chip, a biochip or the like and hasbeen attracting attention as a technology of enabling fast or highlyefficient chemical and biological analysis, integration, andminiaturization for analysis device.

In the μ-TAS, since analysis can be made using a small amount of sampleand the microchip is disposable, the μ-TAS is expected to be applied tobiological analysis that uses a precious sample with minute amount orhandles many samples.

An application example of the μ-TAS includes an optical detectionapparatus that introduces a substance into a plurality of areas arrangedon a microchip and optically detects the substance. Examples of theoptical detection apparatus include an electrophoresis apparatus thatseparates a plurality of substances from a flow channel on a microchipby electrophoresis and optically detects the separated substance; and areaction apparatus (for example, a realtime PCR apparatus) thatprogresses reaction between a plurality of substances in a well on amicrochip and optically detects the generated substance.

For example, Japanese Unexamined Patent Application Publication No.2009-284769 discloses a micro substrate provided with a sample inletpart that introduces a sample and a plurality of storage parts thatstore the sample; and a plurality of exhaust parts which arerespectively connected to the storage parts. Specifically, the microsubstrate has a flow channel structure in which a sample inlet part iscommunicated with each storage part through a main flow channel and aplurality of branch flow channels branched from the main flow channel.

SUMMARY

In a microchip, in a case where there are a plurality of storing areas(analysis areas) of a sample which are connected to an inlet part of asample solution through a flow channel, in general, the sample solutionfills the analysis areas starting from the analysis area which ispositioned closest to the inlet part depending on the flow channelstructure. For this reason, there is a possibility that fluctuationoccurs in the analysis areas at the completion time of filling with thesolution. Accordingly, there is a possibility that fluctuation occursduring reaction in the analysis areas when reaction is caused in theanalysis areas and an object for analysis is produced.

In the present technology, it is desirable to provide a microchipcapable of suppressing the fluctuation in the plurality of analysisareas at the completion time of filling the plurality of analysis areaswith a liquid.

According to an embodiment of the present technology, there is provideda microchip including an inlet part to which a liquid is injected; aplurality of analysis areas to which the liquid is supplied from theinlet part; and a flow channel which is formed to supply the liquid tothe plurality of analysis areas at the same time.

Since the microchip according to the embodiment of the presenttechnology includes a flow channel which is formed to supply the liquidto the plurality of analysis areas from the inlet part at the same time,when the liquid is injected to the inlet part, the liquid flows reacheach of the analysis areas at the same time.

The flow channel may be formed in a way such that flow channelresistances from the inlet part to each of the analysis areas aresubstantially the same as each other, and therefore, it is possible tosupply the liquid to each of the analysis areas at the same time.

The flow channel may include a main flow channel connected to the inletpart and a plurality of branch flow channels which are branched from themain flow channel and are connected to each of the analysis areas.

It is preferable that a cross-sectional area perpendicular to the flowdirection of the liquid in the main flow channel be larger than a totalcross-sectional area perpendicular to the flow direction of the liquidin the plurality of branch flow channels.

It is preferable that, in the plurality of analysis areas, the flowchannel be formed in a way such that a flow channel resistance of afirst branch flow channel which is connected to a first analysis areapositioned closest to the inlet part and a flow channel resistance froma connection point of the first branch flow channel in the main flowchannel to other analysis areas instead of the first analysis area aresubstantially the same as each other.

The microchip may include the plurality of the main flow channels whichmay be formed in a way such that flow channel resistances of each of themain flow channels from the inlet part to analysis areas positionedclosest to the inlet part are substantially the same as each other.

The microchip may include a second flow channel through which the liquidflows out from the analysis areas; and a display area which is connectedto each of the analysis areas through the second flow channel andpresents supplying status of a liquid to each of the analysis areas.

The second flow channel may include a plurality of second branch flowchannels connected to each of the analysis areas and a second main flowchannel connected to the plurality of second branch flow channels.

The second main flow channel may be formed in a way such that the widthand/or the depth of a cross-section perpendicular to the flow directionof the liquid in the second main flow channel increase gradually or in astepwise manner toward the display area.

A storage part for preventing backflow of the liquid may be provided ina predetermined position of the second flow channel.

A reagent reservoir area may be provided separately from the analysisareas between the inlet part and the analysis areas.

In the configuration in which the flow channel is formed in a way suchthat flow channel resistances from the inlet part to each of theanalysis areas are substantially the same as each other, the flowchannel resistance may be derived from resistance elements such as theviscosity of the liquid, the length of the flow channel, and the size ofa cross-section perpendicular to the flow direction of the liquid in theflow channel.

For example, in a case where the cross-section perpendicular to the flowdirection of the liquid in the flow channel has a rectangular shape, theflow channel resistance in the flow channel may be calculated by thefollowing Formula (I).

$\begin{matrix}{R = {\frac{12\eta \; L}{1 - {0.63( {h\text{/}w} )}} \cdot \frac{1}{h^{3}w}}} & (I)\end{matrix}$

(In Formula (I) described above, R represents the flow channelresistance [Pa·s/mm³] of the flow channel, η represents the dynamicviscosity [Pa·s] of the liquid, L represents the length [mm] of the flowchannel, h represents the depth [mm] of the flow channel, and wrepresents the width [mm] of the flow channel.)

In the configuration including a constriction part in the branch flowchannel, the constriction part may be formed in a way such that flowchannel resistances from the inlet part to each of the analysis areasare substantially the same as each other.

A resistant part against the flow of the liquid may be provided in thebranch flow channel, in which the resistant part may be formed in a waysuch that flow channel resistances from the inlet part to each of theanalysis areas are substantially the same as each other.

According to another embodiment of the present technology, there isprovided a method of manufacturing a microchip including: forming a flowchannel, through which a liquid can be supplied to a plurality ofanalysis areas from an inlet part to which the liquid is injected at thesame time, in a substrate.

According to the embodiments of the present technology, there isprovided a microchip capable of suppressing the fluctuation at thecompletion time of filling in the plurality of analysis areas with theliquid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view schematically illustrating a microchip according toa first embodiment of the present technology;

FIGS. 2A and 2B are cross-sectional views schematically illustrating amicrochip of a first embodiment, in which FIG. 2A is a cross-sectionalview taken along line IIA-IIA of FIG. 1 and FIG. 2B is a cross-sectionalschematic view taken along line IIB-IIB of FIG. 1;

FIG. 3A is an enlarged view of an area IIIA in FIG. 2B and FIGS. 3B to3F are views corresponding to FIG. 3A for illustrating modificationexamples of cross-sectional shapes of flow channels;

FIG. 4 is a top view schematically illustrating a microchip according toa second embodiment of the present technology;

FIG. 5 is a top view schematically illustrating a microchip of a firstmodification example according to a second embodiment of the presenttechnology;

FIG. 6 is a top view schematically illustrating a microchip of a secondmodification example according to a second embodiment of the presenttechnology;

FIG. 7 is a top view schematically illustrating a microchip according toa third embodiment of the present technology;

FIG. 8 is a top view schematically illustrating a microchip according toa fourth embodiment of the present technology;

FIG. 9 is a top view schematically illustrating a microchip of a firstmodification example according to a fourth embodiment of the presenttechnology;

FIG. 10 is a top view schematically illustrating a microchip of a secondmodification example according to a fourth embodiment of the presenttechnology;

FIG. 11 is a view illustrating a microchip according to a fifthembodiment of the present technology and is a schematic view partiallyshowing a top view of the microchip;

FIG. 12 is a view illustrating a microchip of a modification exampleaccording to a fifth embodiment of the present technology and is aschematic view partially showing a top view of the microchip;

FIG. 13 is a view illustrating examples of manufacturing a branch flowchannel in a microchip according to modification examples of a fifthembodiment of the present technology;

FIGS. 14A to 14C are views illustrating another example of manufacturinga branch flow channel in a microchip according to modification examplesof a fifth embodiment of the present technology;

FIGS. 15A and 15B are views illustrating a microchip according to asixth embodiment of the present technology;

FIG. 16 is a view illustrating a microchip used in an example; and

FIGS. 17A and 17B are views illustrating test results according to anexample and a comparative example.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, the preferred embodiments for implementing the presenttechnology are described. Note that the embodiments described belowillustrate typical embodiments of the present technology and this doesnot limit the scope of the present technology. In addition,configurations that are common in each embodiment described below aregiven of the same reference numerals and the same description will notbe repeated.

Embodiments are described as follows.

1. First Embodiment

(A configuration example in which flow channel resistances from an inletpart to each of analysis areas are substantially the same as each other)

2. Second Embodiment

(A configuration example in which the length of a flow channel from aninlet part to each of analysis areas are substantially the same as eachother)

3. Third Embodiment

(A configuration example including a plurality of main flow channelshaving a plurality of branch flow channels)

4. Fourth Embodiment

(A configuration example including a second flow channel through which aliquid flows out from an analysis area)

5. Fifth Embodiment

(A configuration example including a constriction part or a resistantpart in a flow channel)

6. Sixth Embodiment

(A configuration example including a reagent reservoir area between aninlet part and analysis areas)

First Embodiment

FIG. 1 is a top view schematically illustrating a microchip 11 accordingto a first embodiment of the present technology. FIGS. 2A and 2B arecross-sectional views schematically illustrating a microchip 11, inwhich FIG. 2A is a cross-sectional view taken along line IIA-IIA of FIG.1 and FIG. 2B is a cross-sectional schematic view taken along lineIIB-IIB of FIG. 1. In addition, FIG. 3A is an enlarged view of an areaIIIA in FIG. 2B and FIGS. 3B to 3F are views corresponding to FIG. 3Afor illustrating modification examples of cross-sectional shapes of flowchannels to be described.

As illustrated in FIG. 1, the microchip 11 of the first embodimentincludes an inlet part 12 to which a liquid is injected; a plurality ofanalysis areas 13; and a flow channel 14 which is formed to be connectedto the inlet part 12 and the analysis areas 13 and to supply the liquidto the analysis areas 13 from the inlet part 12 at the same time.Moreover, the flow channel 14 is formed in a way such that the liquid issupplied to the plurality of analysis areas 13 from the inlet part 12 atthe same time.

Substrate

An inlet part 12, analysis areas 13, and a flow channel 14 are formed asa space in a substrate 110 that configures a microchip 11. Theconfiguration of the substrate 110 that forms the microchip 11 is notparticularly limited. For example, the substrate can be configured tohave a plurality of substrate layers. Although FIGS. 2A and 2B show anexample of two substrate layers 111 and 112, the number of substratelayer may be three or more. In addition, FIGS. 2A and 2B show an exampleof a configuration where the inlet part 12 or the like is formed in thesubstrate layer 112.

As a material of the substrate 110, glass, a resin material(polypropylene, polycarbonate, polymethyl methacrylate, or the like),and various elastomer materials (natural rubber, synthetic rubber suchas polydimethylsiloxane, and thermoplastic elastomer or the like) areused. For example, it is possible to configure the microchip 11 in a waysuch that the inlet part 12, the analysis areas 13 and the flow channel14 are formed as a substrate layer made of a resin and a substrate layermade of elastomer that blocks the inlet part 12 is superimposed thereon.

In a case of optically analyzing an object of analysis in the analysisareas 13, it is preferable to select a material that has opticaltransparency and has a small optical error with little intrinsicfluorescence and small wavelength dispersion, as the material of thesubstrate 110.

It is possible to mold the inlet part 12, the analysis areas 13, theflow channel 14 or the like for the substrate 110 using methods such aswet etching or dry etching of a substrate layer made of glass andnanoimprinting, injection molding, or cutting of a substrate layer madeof resin. It is possible to bond the substrate 110 using a bondingagent, an adhesive, thermal fusion, anodic bonding, ultrasonic fusion,and the like. In addition, it is also possible to bond the surface ofthe substrate 110 by activating the surface using an oxygen plasmatreatment or a vacuum ultraviolet ray treatment.

Inlet Part

The inlet part 12 is a part to which a liquid used for analysis using amicrochip 11 is injected. The inlet part may be a part of a flow channel(for example, near the end of the flow channel length in the flowchannel) in terms of the inlet part being a part to which the liquid isinjected.

The liquid injected to the inlet part 12 flows into the microchip 11from the inlet part 12.

The way of injecting the liquid to the inlet part 12 is not particularlylimited, but it is possible to inject the liquid using a syringe throughan opening which is made in an injection part (not shown) to communicatewith the outside, for example. In addition, for example, the liquid maybe injected to the inlet part 12 in a way such that the inlet part 12 isblocked using a substrate layer 111 and the substrate layer 111 ispunctured with a puncture member such as a needle connected to asyringe. In a case of performing the puncture injection through thesubstrate layer 111 that blocks the inlet part 12, a substrate layersuch as polyurethane elastomer, polydimethylsiloxane or the like havinga self-sealing property is suitably used as the substrate layer 111 tobe punctured.

Examples of the liquid introduced to the microchip according to anembodiment of the present technology typically include a solutioncontaining an object of analysis or a solution containing a substancethat generates an object of analysis by reacting with other substance.Examples of the object of analysis include a nucleic acid such as DNAand RNA, and a protein containing peptide or antibodies. In addition, abiological reagent itself such as blood containing the object ofanalysis, or a diluted solution of the biological reagent may be used asthe liquid introduced to the microchip according to an embodiment of thepresent technology.

Analysis Areas

Analysis areas 13 are areas to which a liquid injected to an inlet part12 is supplied through a flow channel 14 to be described. A substancecontained in a liquid or a reaction product generated from reaction witha substance as the other substance is detected or analyzed as an objectof analysis in the analysis areas 13. Accordingly, there is a case wherean object of analysis is generated by reaction in the analysis areas 13,and therefore, the analysis areas 13 are also called reaction areas 13in some cases.

As an analysis technique using a microchip, for example, there is ananalysis technique using nucleic acid amplification reaction such as aPCR method executing a temperature cycle in the related art and variousisothermal amplification methods which are not accompanied with thetemperature cycle. Examples of the isothermal amplification methodinclude various existing techniques such as an LAMP method, an SMAPmethod and an NASBA method. In addition, reaction accompanied withquantification of an amplification nucleic acid chain such as areal-time PCR (RT-PCR) method or an RT-RAMP method is also included inthe nucleic acid amplification reaction. The microchip according to anembodiment of the present technology is suitably used in an analysisdevice using the nucleic acid amplification reaction and is suitable fora microchip for nucleic acid amplification reaction.

A part of a substance necessary for analysis may be stored in theanalysis areas 13 in advance. For example, it is possible to store areagent necessary for calculating an amplification product in theanalysis areas 13 during the nucleic acid amplification reaction. As thereagent, for example, it is possible to use one reagent or two or morereagents selected from the group including oligonucleotide primers,enzymes, nucleic acids, monomers (dNTP), and reaction buffer solutionsolutes. It is possible to simply start the nucleic acid amplificationreaction only by injecting a sample liquid as the liquid containing anucleic acid to the inlet part of the microchip by the configuration inwhich a reagent such as an oligonucleotide primer is stored in theanalysis areas.

In the first embodiment, each of the analysis areas 13 is linearlyarranged side by side. In addition, the analysis areas 13 are equallyarranged in a way such that the distances between the analysis areas aresubstantially the same as each other. Accordingly, it is possible toinstall more analysis areas 13 with respect to a planar area of themicrochip 11 by arranging the analysis areas 13 at a regular interval.

Flow Channel

The flow channel 14 is connected to the inlet part 12 and each of theanalysis areas 13 and supplies a liquid injected to the inlet part 12 toeach of the analysis areas 13.

In the first embodiment, the flow channel 14 includes a main flowchannel 15 which is connected to the inlet part 12 and a plurality ofbranch flow channel 16 which are branched from the main flow channel 15and are connected to each of the analysis areas 13. The main flowchannel 15 has a length from the inlet part 12 to a connection point P₁₅between the main flow channel and a fifth branch flow channel 165. Eachof the branch flow channels 16 is obliquely branched from the main flowchannel 15 with a predetermined angle (refer to θ of FIG. 1) withrespect to the flow direction (refer to an arrow F_(m) of FIG. 1) in themain flow channel 15, and is connected to each of the analysis areas 13.

Moreover, the flow channel 14 is formed in a way such that the liquid issupplied to the plurality of analysis areas 13 from the inlet part 12 atthe same time. Specifically, the flow channel is formed in a way suchthat flow channel resistances from the inlet part 12 to each of theanalysis areas 13 are substantially the same as each other. By havingsuch a configuration, if the liquid is injected to the inlet part 12,the liquid is supplied to the plurality of analysis areas 13 at the sametime.

Here, the “same time” includes a case where, when the filling of ananalysis area with the liquid is completed, other analysis areas are ina state where greater than or equal to 50% of the analysis areas arefilled with the liquid or suitably in a state in which the filling ofthe analysis areas with the liquid is being finished, as well as a casewhere the liquid is simultaneously supplied to each of the analysisareas.

In addition, the “flow channel resistance” indicates as to how theliquid hardly (easily) flows through the flow channel. The flow channelresistance is based on resistance elements such as the length, thewidth, the depth and the shape of the flow channel, the properties of awall surface in the flow channel, and the viscosity of the liquidflowing in the flow channel.

As described above, the flow channel 14 in the microchip 11 of the firstembodiment of the present technology is formed in a way such that theflow channel resistances in the main flow channel 15 and the branch flowchannel 16 from the inlet part 12 to each of the analysis areas 13 aresubstantially the same as each other with respect to each of theanalysis areas 13. For example, it is possible to form the flow channelin a way such that the flow channel resistances are substantially thesame as each other by changing the lengths of the branch flow channels16 for every branch flow channels 16 by adjusting the widths and depthsof the branch flow channels 16 or the angles θ between the branch flowchannels 16 and the main flow channel 15.

Hereinafter, the flow channel structure is described in more detail.

In the first embodiment, the main flow channel 15 from the inlet part 12to a connection point (first connection point) P₁₁ of a branch flowchannel (first branch flow channel) 161 which is connected to ananalysis area (first analysis area) 131 positioned closest to the inletpart 12 is common with respect to each of the analysis areas 13.Therefore, the flow channel resistance from the inlet part 12 to thefirst connection point P₁₁ is identical with respect to each of theanalysis areas 13.

For this reason, the flow channel resistance of the first branch flowchannel 161 is substantially the same as each flow channel resistance inthe flow channel 14 from the first connection point P₁₁ in the main flowchannel 15 to each of analysis areas 132, 133, 134, and 135 except forthe first analysis area 131.

More specifically, the flow channel resistance of the first branch flowchannel 161 is the same as a total flow channel resistance of the mainflow channel 15 from the first connection point P₁₁ to the secondconnection point P₁₂ and of the second branch flow channel 162 connectedto the second analysis area 132.

Similarly, the flow channel resistance of the first branch flow channel161 is the same as a total flow channel resistance of the main flowchannel 15 from the first connection point P₁₁ to a third connectionpoint P₁₃ and of the third branch flow channel 163.

The same principle also applies to a total flow channel resistance ofthe main flow channel 15 from the first connection point P₁₁ to a fourthconnection point P₁₄ and of a fourth branch flow channel 164, and atotal flow channel resistance of the main flow channel 15 from the firstconnection point P₁₁ to a fifth connection point P₁₅ and of a fifthbranch flow channel 165.

Accordingly, since the microchip 11 is provided with the flow channel 14which is formed in a way such that the flow channel resistances from theinlet part 12 to each of the analysis areas 13 are substantially thesame as each other, it is possible to supply the liquid injected to theinlet part 12 to the plurality of analysis areas 13 at the same time.

The above-described flow channel resistances are derived from resistanceelements such as the viscosity of the liquid flowing through the flowchannel 14, the length of the flow channel 14 from the inlet part 12 toeach of the analysis areas 13, and the form and the size of across-section perpendicular to the flow direction (refer to F_(m) ofFIG. 1) (hereinafter, simply referred to as “vertical section”) of theliquid in the flow channel 14.

Specifically, as shown in the schematic view of the verticalcross-section of the main flow channel 15 of FIG. 3A, the verticalcross-section of the flow channel 14 (main flow channel 15 and branchflow channel 16) has a rectangular shape and the flow channel resistancecan be calculated by the following Formula (I).

$\begin{matrix}{R = {\frac{12\eta \; L}{1 - {0.63( {h\text{/}w} )}} \cdot \frac{1}{h^{3}w}}} & (I)\end{matrix}$

Here, in Formula (I) described above, R represents the flow channelresistance [Pa·s/mm³] of the flow channel, η represents the dynamicviscosity [Pa·s] of the liquid, L represents the length [mm] of the flowchannel, h represents the depth [mm] of the flow channel, and wrepresents the width [mm] of the flow channel.

The flow channel resistances are respectively calculated in the mainflow channel 15 and the branch flow channels 16 for every flow channels14 having different sizes. In a case of calculating the flow channelresistance of the main flow channel 15, in the above-described Formula(I), R is a flow channel resistance of the main flow channel 15, L is alength of the main flow channel 15, and h and w are respectively a depthand a width of the main flow channel 15 (refer to FIG. 3A). Furthermore,in a case of calculating the flow channel resistance of the branch flowchannel 16, in the above-described Formula (I), R is a flow channelresistance of the branch flow channel 16 and L, h, and w arerespectively a length, a depth, and a width of the branch flow channel16 to be calculated.

More specifically, for example, the flow channel resistance from theinlet part 12 to the first analysis area 131 is obtained from summing upthe flow channel resistance of the main flow channel 15 from the inletpart 12 to the first connection point P₁₁ and the flow channelresistance of the first branch flow channel 161.

Accordingly, the flow channel resistances from the inlet part 12 to eachof the analysis areas 13 are obtained from summing up the flow channelresistances in each main flow channel 15 from the inlet part 12 to eachof the connection points (P₁₁ to P₁₅) of the branch flow channels 16connected to each of the analysis areas 13, and the flow channelresistances of each of the branch flow channels 16.

As described above, the flow channel structure in the microchip of thefirst embodiment is formed in a way such that the flow channelresistances from the inlet part 12 to each of the analysis areas 13 aresubstantially the same as each other between the analysis areas 13(between the flow channels 14 from the inlet part 12 to each of theanalysis areas 13).

Here, in an embodiment of the present technology, “substantially thesame” flow channel resistances refers that each of the calculated flowchannel resistance values are substantially within the same range. Forexample, in a case where the difference between the maximum value andthe minimum value among each of the flow channel resistances from theinlet part 12 to each of the analysis areas 13 is within 5%, preferablywithin 2%, and more preferably within 1%, with respect to an averagevalue of each of the flow channel resistances, the flow channelresistances are considered to be substantially the same as each other.

In addition, the microchip 11 of the first embodiment is formed in a waysuch that the area of the vertical cross-section of the main flowchannel 15 is larger than the total area of the vertical cross-sectionsof the branch flow channels 16. Accordingly, it is possible to supply aliquid to the plurality of branch flow channels 16 branched from themain flow channel 15 at a sufficient flow rate.

Regarding the vertical cross-sections of the flow channel 14, it ispossible adjust the flow channel resistances from the inlet part 12 toeach of the analysis areas 13 and to change the width and/or the depthof the vertical cross-sections of the branch flow channels 16 for everybranch flow channels.

For example, it is possible to increase the width and/or the depth ofthe vertical cross-sections of the plurality of branch flow channels 16,as the branch flow channel 16 is positioned in the downstream side (asthe branch flow channel 16 is positioned farther from the inlet part12). Specifically, it is possible to increase the width and/or the depthof a branch flow channel 16 positioned in the downstream side (forexample, the fifth branch flow channel 165) in the verticalcross-section more than the width and/or the depth of a branch flowchannel 16 positioned in the upstream side (for example, the firstbranch flow channel 161) in the vertical cross-section.

Accordingly, it is possible to adjust each of the flow channelresistances from the inlet part 12 to each of the analysis areas 13 bymaking the liquid easily flow (difficult to receive resistance) inbranch flow channels 16 as the branch flow channel is positioned fartherfrom the inlet part 12. In this case, it is suitable that the flowchannel resistance of the branch flow channel 16 becomes smaller as thebranch flow channel is positioned further on the downstream side thanthe upstream side.

The shape of the vertical cross-section of the flow channel 14 may be asquare shape, a circular shape, an elliptical shape, a triangular shape,and parabolic shape (a shape having a parabola) in addition to therectangular shape (refer to FIGS. 3A to 3F). Even if the shape of thevertical cross-section of the flow channel 14 is a shape other than therectangular shape, it is possible to calculate the flow channelresistance according to the shape of the flow channel using theresistance elements described above.

In a case where the shape of the vertical cross-section of the flowchannel is in a square shape, the flow channel resistance can becalculated using the following Formula (II) (refer to FIG. 3B).

$\begin{matrix}{R = {28.4\eta \; L\frac{1}{h^{4}}}} & ({II})\end{matrix}$

In Formula (II) described above, R represents the flow channelresistance [Pa·s/mm³] of the flow channel in a case where the verticalcross-section is the square shape, η represents the dynamic viscosity[Pa·s] of the liquid, L represents the length [mm] of the flow channel,and h represents the depth or the width [mm] of the flow channel in thevertical cross-section.

In a case where the shape of the vertical cross-section of the flowchannel is in a circular shape, the flow channel resistance can becalculated using the following Formula (III) (refer to FIG. 3C).

$\begin{matrix}{R = {\frac{8}{\pi}\eta \; L\frac{1}{a^{4}}}} & ({III})\end{matrix}$

In Formula (III) described above, R represents the flow channelresistance [Pa·s/mm³] of the flow channel in a case where the verticalcross-section is the circular shape, η represents the dynamic viscosity[Pa·s] of the liquid, L represents the length [mm] of the flow channel,and a represents the radius [mm] of the flow channel in the verticalcross-section.

In a case where the shape of the vertical cross-section of the flowchannel is an elliptical shape, the flow channel resistance can becalculated using the following Formula (IV) (refer to FIG. 3D).

$\begin{matrix}{R = {\frac{4}{\pi}\eta \; L\; {\frac{1 + ( {b\text{/}a} )^{2}}{( {b\text{/}a} )^{3}} \cdot \frac{1}{a^{4}}}}} & ({IV})\end{matrix}$

In Formula (IV) described above, R represents the flow channelresistance [Pa·s/mm³] of the flow channel in a case where the verticalcross-section is in an elliptical shape, η represents the dynamicviscosity [Pa·s] of the liquid, and L represents the length [mm] of theflow channel. In addition, a and b respectively represent a semi-majoraxis (major axis radius) [mm] and a semi-minor axis (minor axis radius)[mm] of the flow channel in the vertical cross-section.

In a case where the shape of the vertical cross-section of the flowchannel is in an equilateral triangular shape, the flow channelresistance can be calculated using the following Formula (V) (refer toFIG. 3E).

$\begin{matrix}{R = {\frac{320}{\sqrt{3}}\eta \; L\frac{1}{a^{4}}}} & (V)\end{matrix}$

In Formula (V) described above, R represents the flow channel resistance[Pa·s/mm³] of the flow channel in a case where the verticalcross-section is the equilateral triangular shape, η represents thedynamic viscosity [Pa·s] of the liquid, L represents the length [mm] ofthe flow channel, and a represents the length [mm] of a side in thevertical cross-section of the flow channel.

In a case where the shape of the vertical cross-section of the flowchannel is in a parabolic shape, the flow channel resistance can becalculated using the following Formula (VI) (refer to FIG. 3F).

$\begin{matrix}{R = {\frac{105}{4}\eta \; L\frac{1}{h^{3}w}}} & ({VI})\end{matrix}$

In Formula (VI) described above, R represents the flow channelresistance [Pa·s/mm³] of the flow channel in a case where the verticalcross-section is the parabolic shape, η represents the dynamic viscosity[Pa·s] of the liquid, and L represents the length [mm] of the flowchannel. In addition, h represents the length [mm] of a parabola in thevertical cross-section and w represents the length [mm] of the linearportion in the vertical cross-section.

In the microchip 11 of the first embodiment described above, it ispossible to supply the liquid injected to the inlet part 12 to theplurality of analysis areas 13 at the same time by forming the microchipin a way such that the flow channel resistances from the inlet part 12to each of the analysis areas 13 are substantially the same as eachother. Accordingly, it is possible to suppress the fluctuation incompletion time of filling with the liquid between the analysis areas13.

Accordingly, in a case where the object of analysis in the analysis area13 is a substance which is generated accompanied with chemical reactionby the supply of the liquid, it is possible to adjust the reaction startcondition in each of the analysis areas 13 and to reduce the fluctuationof the reaction. For example, in a case where a reagent is stored in theanalysis areas 13 in advance and the reagent is dissolved in a liquidsupplied to the analysis areas 13 to generate reaction, it is possibleto adjust the dissolution time and to reduce the fluctuation of thereaction.

Meanwhile, in the microchip of the related art that does not have theflow channel structure in which a liquid is supplied to each analysisarea at the same time, there is a fluctuation in the completion time offilling the analysis areas with the liquid causing contamination betweenthe analysis areas or fluctuation in the amount of the liquid, in somecases. In addition, in a case where reagents are stored in the analysisareas in advance and the reagents are dissolved in a liquid to generatereaction, there is a possibility that the reagents cause nonspecificreaction (primer dimer or the like) in the analysis areas in which thereagents are dissolved in advance.

It is possible to solve such problems using the flow channel structurein which the microchip according to an embodiment of the presenttechnology is formed in a way such that the flow channel resistancesfrom the inlet part to each of the analysis areas are substantially thesame as each other.

In addition, it is possible to supply a liquid to the plurality ofbranch flow channels 16 at a sufficient flow rate by forming themicrochip 11 of the first embodiment in a way such that the area of thevertical cross-section of the main flow channel 15 is larger than thetotal area of the vertical cross-sections of the plurality of branchflow channels 16. Accordingly, it is possible to obtain the microchip 11in which the simultaneous supply of the liquid to the plurality ofanalysis areas 13 can be more easily realized.

Furthermore, each length of the flow channel from the inlet part 12 toeach of the analysis areas 13 is different in the microchip 11. However,by providing the flow channel structure in which the flow channelresistances are substantially the same as each other, it is possible tostore the flow channel group with space saved compared to a structure inwhich the distances from an inlet part to each of analysis areas are thesame as each other. For this reason, in the microchip 11 of the firstembodiment, it is possible to arrange high density analysis areas inmultiple numbers.

Second Embodiment

FIG. 4 is a top view schematically illustrating a microchip 21 accordingto a second embodiment of the present technology.

Similarly to the first embodiment, the microchip 21 of the secondembodiment includes an inlet part 22; a plurality of analysis areas 23;and a flow channel 24 which is connected to the inlet part 22 and theanalysis areas 23.

Since the description of the inlet part 22 and the analysis areas 23 isthe same as the description provided in the first embodiment except forthe arrangement position and the arrangement number, the descriptionwill not be repeated in the following embodiments and modificationexamples.

Similarly to the microchip 11 of the first embodiment, the microchip 21of the second embodiment has the flow channel 24 which is formed in away such that the liquid is supplied from the inlet part 22 to theplurality of analysis areas 23 at the same time. In addition, similarlyto the flow channel 14 of the microchip 11, the flow channel 24 in themicrochip 21 is formed in a way such that flow channel resistances fromthe inlet part 22 to each of the analysis areas 23 are substantially thesame as each other.

However, the microchip 21 of the second embodiment is different from theflow channel structure in the microchip 11 of the first embodiment inthat the lengths of the flow channels 24 from the inlet part 22 to eachof the analysis areas 23 are formed to be substantially the same as eachother with respect to the analysis areas 23.

As shown in FIG. 4, the microchip 21 has a main flow channel 25 and aplurality of branch flow channels 26 branched from the main flow channel25, and the microchip is provided with a plurality of main flow channels25.

Moreover, each of first branch flow channels 261 which is branched fromeach of the main flow channels 25 and is connected to each of firstanalysis areas 231 positioned in a row closest to the inlet part 22 hasa bellows shape in planar view. In addition, each of second branch flowchannels 262 which is branched from each of the main flow channels 25and is connected to each of second analysis areas 232 positioned in amiddle row has a bellows shape in planar view with less foldingfrequencies than the first branch flow channel 261. Furthermore, each ofthird branch flow channels 263 which is connected to each of thirdanalysis areas 233 positioned in a row farthest to the inlet part 22,from each of the main flow channels 25 is linearly and obliquely formedfrom each of the main flow channels 25.

Each of main flow channels 251, 252, and 253 is formed in a way suchthat the lengths from the inlet part 22 to each of the first branch flowchannels 261 are substantially the same as each other. Here, each of themain flow channels 25 is a flow channel having a length from the inletpart 22 to a position in which the third branch flow channel 263 isbranched.

Moreover, the lengths of the first branch flow channels 261 are formedto be substantially the same as each other. In addition, the lengths ofthe second branch flow channels 262 and the lengths of the third branchflow channels 263 are respectively formed to be substantially the sameas each other.

As described above, the microchip 21 of the second embodiment is formedin a way such that the lengths of the flow channels 24 from the inletpart 22 to each of the analysis areas 23 are substantially the same aseach other by making the shapes of the main flow channels 25 and thebranch flow channels 26 different from each other in planar view.

In addition, the microchip 21 is formed in a way such that the widthsand the depths of the vertical cross-section of the flow channels 24 arethe same as each other in addition to the lengths of the flow channels24 from the inlet part 22 to each of the analysis areas 23. By havingsuch a configuration, the flow channels 24 in the microchip 21 areformed in a way such that the flow channel resistances from the inletpart 22 and each of the analysis areas 23 are substantially the same aseach other.

In FIG. 4, only the analysis areas 23 (231, 232, and 233) thatcommunicate with the main flow channel 251 are given of referencenumerals to show the drawing clear. However, the other analysis areasthat respectively communicate with the main flow channels 252 and 253are also given of the same reference numerals. In addition, in FIG. 4,only the branch flow channels 26 (261, 262, and 263) which are branchedfrom the main flow channel 253 are given of reference numerals to showthe drawing clear. However, the other branch flow channels which arerespectively branched from the main flow channels 251 and 252 are alsogiven of the same reference numerals.

The microchip 21 of the second embodiment described above is formed in away such that the lengths, the widths, and the depths of the flowchannels 24 from the inlet part 22 to each of the analysis areas 23 aresubstantially the same as each other, and thus, the flow channelresistances from the inlet part 22 to each of the analysis areas aresubstantially the same as each other. Accordingly, it is possible tosupply the liquid injected to the inlet part 22 to the plurality ofanalysis areas 23 at the same time.

The microchip 21 of the second embodiment is formed in a way such thatthe resistance elements based on the flow channels in terms of thelengths, the widths, and the depths of the flow channels 24 connected toeach of the analysis areas 23 from the inlet part 22 are the same aseach other between each of the analysis areas 23. For this reason,according to the microchip 21, it is possible to suppress thefluctuation in completion time of filling each of the analysis areas 23with the liquid without accurately controlling the resistance elementsof the plurality of main flow channels 25 and branch flow channels 26.Furthermore, in a case where chemical reaction is generated in theanalysis areas 23, it is possible to reduce the fluctuation of thereaction between each of the analysis areas 23.

Modification Example of Second Embodiment

FIGS. 5 and 6 are views illustrating, as a modification example of thesecond embodiment, examples of configuring a microchip which is formedin a way such that the lengths of the flow channels from the inlet partto each of the analysis areas are substantially the same as each otherwith respect to the analysis areas.

In a microchip 21A of a first modification example shown in FIG. 5, aplurality of analysis areas 23 a are provided through a plurality offlow channels 24 a installed from an inlet part 22 a in a radialpattern. Moreover, the microchip 21A is formed in a way such that thelengths, the widths, and the depths of the flow channels 24 a aresubstantially the same as each other.

In addition, in a microchip 21B of a second modification example shownin FIG. 6, branch flow channels 26 b are formed to be connected to eachof analysis areas 23 b in a radial pattern from a connection point P₂₁which is positioned at a predetermined distance from an inlet part 22 bin a main flow channel 25 b connected to the inlet part 22 b. Moreover,the microchip 21B is formed in a way such that the lengths of the branchflow channels from the connection point P₂₁ to each of the analysisareas 23 b are the same as each other, and thus, the lengths of flowchannels 24 b from the inlet part 22 b to each of the analysis areas 23b are the same as each other.

The microchips 21A and 21B shown in FIGS. 5 and 6 described above alsoexhibits the same effect as in the microchip 21 of the secondembodiment.

Third Embodiment

FIG. 7 is a top view schematically illustrating a microchip 31 accordingto a third embodiment of the present technology.

The microchip 31 of the third embodiment is configured to have the flowchannel structure of the first embodiment and the flow channel structureof the second embodiment in combination.

Similarly to the microchip 11 of the first embodiment, the microchip 31of the third embodiment has a main flow channel 35 connected to an inletpart 32 and a plurality of branch flow channels 36 connected to each ofanalysis areas 33 branched from the main flow channel 35. Moreover, themicrochip 31 of the third embodiment includes a plurality of the mainflow channels 35 provided with the plurality of branch flow channels 36.FIG. 7 illustrates an example of a flow channel structure including fivemain flow channels 351, 352, 353, 354, and 355 and five branch flowchannels 361, 362, 363, 364, and 365 branched from each of the main flowchannels 35.

The flow channel resistance of the main flow channel 35 from the inletpart 32 to a first connection point P₃₁ of a first branch flow channel361 positioned closest to the inlet part 32 in a main flow channel 35 isformed to be substantially the same between the main flow channels 351,352, 353, 354, and 355. Specifically, the length of the main flowchannel 35 from the inlet part 32 to the first connection point P₃₁ andthe width and the depth of the vertical cross-section of the main flowchannel 35 is formed to be substantially the same between the main flowchannels 351, 352, 353, 354, and 355.

In addition, similarly to the first embodiment, the flow channel 34 isformed in a way such that the flow channel resistance of the firstbranch flow channel 361 positioned closest to the inlet part 32 in amain flow channel 35 is substantially the same as each flow channelresistance from the first connection point P₃₁ to analysis areas 33except for the first analysis area 331. The flow channel resistance ofthe first branch flow channel 361 and each of the flow channelresistances from the first connection point P₃₁ to the second to thefifth analysis areas 332, 333, 334, and 335 can be calculated by any ofFormulas (I) to (VI) according to the shape of the verticalcross-section of the flow channel.

As described above, the microchip 31 of the third embodiment is formedin a way such that the lengths, the widths, and the depths of each ofthe main flow channels 35 from the inlet part 32 to the first connectionpoints P₃₁ are substantially the same as each other. Furthermore, theflow channels 34 from the first connection points P₃₁ to the second tothe fifth analysis areas 332 to 335 are formed in a way such that theflow channel resistances calculated using the resistance elements basedon the shape of the flow channels 34 and the dynamic viscosity of theliquid when the liquid flows through the flow channels are substantiallythe same as each other. In the microchip 31 according to the thirdembodiment having such a configuration, it is possible to arrange highdensity analysis areas 33 in multiple numbers to which the liquid issupplied from the inlet part 32 at the same time compared to themicrochip 21 of the second embodiment, in an identical planar area. Forthis reason, in the microchip 31 of the third embodiment, it is possibleto increase the number of analysis results by supplying the liquid once,thereby enhancing the efficiency of the analysis. The microchip 31 ofthe third embodiment also exhibits the same effect as that of themicrochip 11 of the first embodiment.

Fourth Embodiment

A microchip according to an embodiment of the present technology mayseparately have a second flow channel through which a liquid flows outfrom an analysis area in addition to a flow channel supplying the liquidto the analysis area from an inlet part. An example of the configurationprovided with the second flow channel is shown in FIG. 8 as a top viewschematically illustrating a microchip according to a fourth embodimentof the present technology.

As shown in FIG. 8, the microchip 41 of the fourth embodiment isdifferent from that of the first embodiment in that a configuration of adisplay area 43 and a second flow channel 44 is added to the microchip11 of the first embodiment. In the fourth embodiment, a configurationwhich is common in the first embodiment is given of the same referencenumerals and the description will not be repeated.

The microchip 41 of the fourth embodiment includes a second flow channel44 and a display area 43 connected to each of analysis areas 13 throughthe second flow channel 44 and is configured in a way such that a liquidpassed through each of the analysis areas 13 flows into the display area43 through the second flow channel 44.

In addition, the second flow channel 44 has a second main flow channel45 and a plurality of second branch flow channels 46 (461, 462, 463,464, and 465). The second flow channel 44 has the second branch flowchannel 46 through which the liquid flows out from each of the analysisareas 13 for every analysis area 13. In addition, the second flowchannel 44 is connected to the display area 43 through the second mainflow channel 45 in a way such that the plurality of second branch flowchannels 46 join the second main flow channel 45 by being connectedthereto.

Display Area

The display area 43 presents supplying status of a liquid to each of theanalysis areas 13 (131, 132, 133, 134, and 135) and is formed as a spacein a substrate that configures the microchip similarly to the analysisareas 13 or the like.

The display area 43 is configured in a way such that a user can visuallyrecognize that the liquid reaches the display area 43. The arrival ofthe liquid at the display area 43 takes place after the completion ofthe filling of the analysis areas 13 with the liquid connected to thesecond flow channel 44. For this reason, the arrival of the liquid atthe display area 43 presents the completion of the filling of theanalysis areas 13 with the liquid. Conversely, no arrival of the liquidat the display area 43 presents that the filling of the analysis areas13 with the liquid is not completed.

The presentation of the supplying status of the liquid to the analysisareas 13 using the display area 43 can be realized by a coloringmaterial or a concave and convex structure which is installed in thedisplay area 43 in advance. In order for a user to visually recognizethe supplying status of the liquid using the display area 43 from theouter surface of the microchip 41, it is preferable to select a materialhaving optical transparency for a substrate layer constituting themicrochip 41.

The confirmation that the liquid reached the display area 43 may beimplemented using a detector such as a photodetector instead of beingvisually checked by a user.

The above-described coloring material stored in the display area 43 inadvance is a material containing a pigment that makes a user easilyrecognize the liquid by color development or discoloration occurred whenthe coloring material comes into contact with the liquid injected to theinlet part 12. Accordingly, the display area 43 presents the arrival ofthe liquid at the display area 43 by the change such as the colordevelopment or the discoloration of the coloring material occurred whenthe coloring material comes into contact with the liquid.

The above-described concave and convex structure installed in thedisplay area 43 in advance presents the arrival of the liquid at thedisplay area 43 using light which is reflected to the concave and convexstructure.

In the microchip 41 of the fourth embodiment, the above-describeddisplay area 43 can be replaced with a discharge outlet of a liquid in acase where a liquid is pressure-injected from the inlet part or anoverflow storage area to completely fill the analysis areas 13 with theliquid. It is possible for contamination to hardly occur by providingthe discharge outlet and it is possible to easily fill the analysisareas 13 with the liquid by providing the overflow storage area.

In the microchip 41 of the fourth embodiment, by providing the secondflow channel 44 and the display area 43 further on a downstream sidethan the analysis areas 13, the analysis areas 13 do not become endportions into which the liquid flows. Such a configuration hassignificant implications in an embodiment of the present technologyhaving a flow channel structure in which a liquid is supplied to theplurality of analysis areas 13 at the same time. That is, it is possibleto simultaneously prevent the backflow of the liquid when the liquid issupplied to the analysis areas 131 to 135 at substantially the sametime. That is, it is possible to simultaneously prevent the backflow ofthe liquid when the liquid is supplied to each of the analysis areas 131to 135 at substantially the same time.

From the viewpoint of preventing the backflow described above, it ispreferable that the second main flow channel 45 be formed in a way suchthat the width and/or the depth of the vertical cross-section increasegradually or in a stepwise manner toward the display area 43. In FIG. 8,the width of the second main flow channel 45 is primarily formed at aposition connected to the second branch flow channel 464 connected tothe analysis area 134 and the second main flow channel 45 continues upto the display area 43 with the enlarged width. In addition, although itis not shown in the drawing, from the viewpoint of preventing thebackflow, a space may be partially provided in the second flow channel44 as a backflow preventative valve.

In the microchip 41 of the fourth embodiment, it is preferable to have aflow channel structure that satisfies the relation “the flow channelresistance of the second branch flow channel 46 (second group) the flowchannel resistance of the first branch flow channel 16 (first group)”.Using the flow channel structure that satisfies the relation, it ispossible to set “the amount of liquid flowing in the analysis area13>the amount of liquid flowing out from the analysis area 13”. For thisreason, even if there is deviation in the timing of supplying the liquidto the analysis areas 13 from the inlet part 12, it is possible toprevent the unevenness due to the contamination or flowing out of theliquid between the analysis areas 13. Accordingly, it is possible toprovide a more high-quality microchip.

Modification Example of Fourth Embodiment

It is possible to change the structure of the microchip 41 of the fourthembodiment that has the display area 43, the second flow channel 44, orthe like as the following.

Respective FIGS. 9 and 10 are top views schematically illustratingmicrochips of a first modification example and a second modificationexample of the fourth embodiment.

A microchip 41A of the first modification example is provided withsecond flow channels 44 a through which a liquid flows out from each ofanalysis areas 13 for every analysis area 13 and also is provided withdisplay areas 43 a for every second flow channel 44 a. Accordingly, itis possible to promptly detect any abnormality due to the deviation ofthe supplying timing of the liquid to the analysis areas 13 from theinlet part 12 by installing display areas 43 a for every analysis area13.

A microchip 41B of the second modification example is provided with asecond main flow channel 45 b, a second flow channel 44 b having aplurality of second branch flow channels 46 b and a display area 43connected to the second main flow channel 45 b. Each second branch flowchannel 46 b is provided with a storage area for preventing backflow 43b between the analysis area 13 and the second main flow channel 45 b. Itis possible to prevent the backflow of the liquid using the microchip41B of the second modification example.

Fifth Embodiment

FIG. 11 is a view illustrating a microchip according to a fifthembodiment of the present technology and is a schematic view partiallyshowing a top view of the microchip.

Similarly to the first embodiment, the microchip according to the fifthembodiment includes an inlet part to which a liquid is injected; aplurality of analysis areas 13; and a flow channel that supplies theliquid to the plurality of analysis areas 13 from the inlet part. Inaddition, similarly to the first embodiment, the flow channel includes amain flow channel 55 connected to the inlet part and a plurality ofbranch flow channels 561 and 562 which are branched from the main flowchannel 55 and are connected to each of the analysis areas 13. However,the configuration of the branch flow channels 561 and 562 is differentfrom the configuration of the branch flow channel 16 of the firstembodiment.

In the fifth embodiment, the respective branch flow channels 561 and 562have constriction parts 561 a and 562 a in which the channels arepartially formed narrow. In addition, the fifth embodiment has a flowchannel formed in a way such that the flow channel resistance from theinlet part to each of the analysis areas 13 is adjusted by theconstriction parts 561 a and 562 b in a way such that the flow channelresistances are substantially the same as each other.

By having such a configuration, the microchip according to the fifthembodiment can supply the liquid to the plurality of analysis areas 13from the inlet part at the same time. The constriction parts 561 a and562 b are formed in a way such that the widths and/or the depths of thevertical cross-section with respect to the flow direction (Refer toarrows F_(b1) and F_(b2) of FIG. 11) of the liquid of the branch flowchannels 561 and 562.

The position of the constriction parts 561 a and 562 a in the branchflow channels 561 and 562 is not particularly limited, but it ispreferable that the constriction parts be positioned further on theanalysis area 13 side instead of the main flow channel 55 side to easilycontrol the above-described flow channel resistance. It is preferablethat the constriction parts 561 a and 562 a be installed at a positionadjacent to the analysis area 13.

The microchip according to the fifth embodiment, the lengths of theplurality of branch flow channels 561 and 562 can be set to besubstantially the same as each other. Moreover, the constriction part561 a can be set longer as the analysis area 13 is positioned further onan upstream side which is close to the inlet part, and the constrictionpart 562 a can be set shorter as the analysis area 13 is positionedfurther on a downstream side which is from the inlet part. By havingsuch a configuration, it is possible to supply the liquid to each of theanalysis areas 13 at substantially the same time and to uniformlyinstall high density analysis areas 13.

As described above, in a case where the constriction parts 561 a and 562a are installed in the branch flow channels 561 and 562, the volume flowrate of the liquid is controlled by making the constriction part 561 anarrower and/or by making the constriction part 561 a longer as theanalysis area 13 is positioned where the distance of the flow channelfrom the inlet part to the analysis area 13 is short.

The volume flow rate is the product of the flow rate of the liquidflowing through the flow channel and the cross-sectional area of theflow channel. Since the flow rate is constant, it is possible to controlthe volume flow rate by changing the cross-sectional area of the flowchannel. Two simple systems in which the lengths of the flow channels tothe analysis area can be considered in relation to the control of thevolume flow rate.

In the two systems, the cross-sectional areas of the flow channels arerespectively set to S1 and S2, the lengths thereof are respectively setto L1 and L2 (here, L2=α×L1), and the flow rates of the liquid flowingthrough the flow channels are respectively set to V1 and V2. If it issupposed that the liquid is simultaneously filled in the analysis areasin each of the systems after a certain period of time, S1=α×S2 isderived from Q1=V1×S1×L1, Q2=V2×S2×L2, V1=V2, L2=α×L1, and Q1=Q2.

Accordingly, it is possible to adjust the supply timing of the liquid tothe analysis areas by changing the cross-sectional area of the flowchannel depending on the length of the flow channel.

Modification Example of Fifth Embodiment

As shown in FIG. 12, resistance parts 563 a and 564 a that have aresistive action against the flow of a liquid may be installed in branchflow channels 563 and 564 according to a modification example of thefifth embodiment. It is possible to set the flow channel resistancesfrom an inlet part to each of analysis areas 13 due to the resistanceparts 563 a and 564 a. The resistance parts 563 a and 564 a may beprovided separately from the branch flow channels 563 and 564 and beprovided with the constriction parts 563 b and 564 b in combination asshown in FIG. 12.

As the above-described resistance parts 563 a and 564 a, it is possibleto use pillars having a micro (μm)-order size or a nano (nm)-order sizeand a particle having a micro-order size or a nano-order size, which areinstalled in the branch flow channels 563 and 564. In addition,resistance parts in which the surfaces of the inside of the branch flowchannels 563 and 564 are treated to have hydrophobicity are included asthe resistance parts 563 a and 564 a. The volume flow rate decreases ifthe inside of flow channel is made to be hydrophobic, and inversely, thevolume flow rate increases if the inside of the flow channel is made tobe hydrophilic. Accordingly, it is possible to adjust the timing ofsupplying the liquid to each of the analysis areas 13 from the inletpart by hydrophilic- or hydrophobic-treating the surfaces of the insideof the branch flow channels 563 and 564.

In a case where pillars are installed in the branch flow channels 563and 564 as the resistance parts 563 a and 564 a, the disposition of thepillars in the branch flow channels 563 and 564 can be performed throughan ultraviolet (UV) photolithography process as shown in FIG. 13, forexample. The process is simply described in the following.

First, a conductive metal thin film M1 made of Ti/Au or the like isformed on a substrate B1 that forms pillars using a technique such assputtering (step S51), and a photoresist r is coated on the metal thinfilm M1 (step S52). In a case where pillar patterns are directlyelaborated on the substrate that configures the microchip, a photoresistusing a negative resist in which solubility with respect to a developingliquid of an exposed portion is deteriorated, is preferable as thephotoresist r. In this case, a convex pattern of the pillar is formedthereon. In addition, in a case of molding the substrate using asubstrate on which the pillar patterns are formed as a template, apositive resist in which solubility with respect to a developing liquidof an exposed portion is improved is used. FIG. 13 shows a processexample using the positive resist.

Next, a mask m in which a flow channel and a pillar pattern areinstalled on the photoresist r is disposed, an ultraviolet ray isradiated from the top of the mask (step S53), and then the exposedresist r portion is removed (step S54). Then, Ni plating M2 is installedon the conductive metal thin film M1 by electroplating or the like (stepS55), the remaining resist r is subsequently removed (step S56), andthen anisotropic dry etching is performed thereon (step S57). At thistime, the Ni plating M2 portion remains because it is difficult to beetched by the anisotropic dry etching and the other portion except forthe Ni plating M2 portion is etched. Thereafter, the Ni plating M2 andthe conductive metal thin film M1 are removed and the substrate B1 onwhich fine convex patterns are formed is obtained (step S58). Finally,it is possible to mold a substrate B2 having a pillar structure usingthe substrate B1 as a template (step S59).

Although an example of molding the substrate B2 using a substrate onwhich pillar patterns are formed was illustrated in the above-describedprocess, it is also possible to directly form the pillars on thesubstrate B2.

Since it is possible to control porosity using the pillar gaps, it isconsidered that the flow channel resistance can be easily controlled dueto the formation of the pillars in the flow channel.

The surface of the pillar formed in the flow channel of the microchipcan be made a hydrophobic surface by chemically modifying the surface,and in this case, it is possible to make the surface to have a reversephase chromatograph function. In addition, it is also possible toinstall a micro pore having a nano-order size on the pillar. It ispossible to add a function of removing unnecessary substances in theliquid by an interaction when the liquid introduced into the microchipflows through the pillars having the micro pores in the branch flowchannel.

When installing particles in the branch flow channels 563 and 564 as theresistance parts 563 a and 564 a, the disposition of the particles inthe branch flow channels 563 and 564 can be performed using a processshown in FIG. 14, for example. The process is simply described in thefollowing.

First, in a substrate layer B3 that constitutes a microchip, a rib partB31 is formed in front (upstream side) of a recessed analysis area W3. Asolution D containing a predetermined amount of particles P is drippedin front (upstream side) of the rib part B31 by using the rib part B31as a gathering spot of the particles P (refer to FIG. 14A). At thistime, if the particles P are dispersed into water or a mixture of waterand alcohol, the water or the mixture of water and alcohol is evaporatedafter the dripping and only the particles P remain in the flow channel(refer to FIG. 14B). Thereafter, it is possible to provide a desiredplace with a predetermined amount of particles P by covering with asubstrate layer B4 having a rib part B41 (FIG. 14C). At this time, sincethe particles P are caught by both the rib parts B31 and B41 in theupstream side and the downstream side of the flow channel C3, it ispossible to prevent the particles P from flowing out to other placesusing the particles P having a particle size greater than the widths ofspaces between both the rib parts B31 and B41 and respective substratelayers.

In a case of dripping the solution D into which the particles P aredispersed in a predetermined position of the flow channel C3, it issuitable to surface-treat the predetermined position to provide morehydrophilicity than the surroundings. An example of the surfacetreatment in this case includes plasma irradiation in an oxygen or inertgas (Ar or the like) atmosphere. In a case of hydrophilic-treating onlya desired place, the desired place may be irradiated with plasma using amask in which a pattern is formed, or the like.

In a case of installing particles as the resistance parts 563 a and 564a installed in the branch flow channels 563 and 564, the amount ofparticles to be filled in a place where it is desired to increase theflow channel resistance is set to be large and the amount of particlesto be filled in a place where it is desired to decrease the flow channelresistance is set to be less. Accordingly, it is possible to control thesupply timing of the liquid to each of the analysis areas 13 from theinlet part.

In addition, it is also possible to capture the impurities or to adjustthe reaction liquid when the liquid introduced to the microchip flowsthrough the branch flow channels 563 and 564 having the particles usingparticles having appropriate chemical modification as the particles usedin the resistance parts 563 a and 564 a.

Sixth Embodiment

In the sixth embodiment of the present technology, it is possible toprovide a reagent reservoir area separately from an analysis areabetween an inlet part and the analysis area in the microchips accordingto the above-described embodiments of the present technology.

FIG. 15A is a view schematically illustrating a configuration that has amain flow channel 65 a and a branch flow channel 66 a and is providedwith a reagent reservoir area 67 a, in which a reagent is stored, in thebranch flow channel 66 a between the inlet part (not shown) and theanalysis area 63 a. In addition, FIG. 15B is a view schematicallyillustrating a configuration that has a main flow channel 65 b and abranch flow channel 66 b and is provided with two reagent reservoirareas 67 b and 67 c in the branch flow channel 66 b between the inletpart (not shown) and the analysis area 63 b.

The reagent reservoir areas 67 a to 67 c may be disposed further on anupstream side than the analysis areas 63 a and 63 b not being adjacentto the analysis areas 63 a and 63 b as shown in FIGS. 15A and 15B, andmay be disposed in a position adjacent to the analysis areas 63 a and 63b. It is preferable that the reagent reservoir areas 67 a to 67 c havean arc shape so as not to cause congestion of the flow of the liquid.

In the analysis area 63 a, in a case where the kind of reagent necessaryfor reaction is greater than or equal to two, it is possible to storeone kind of reagent R1 (for example, a primer or the like) in thereagent reservoir area 67 a and to store another one kind of reagent R2(for example, an enzyme or the like) in an analysis area 63 a, forexample (refer to FIG. 15A).

In addition, it is possible to install the reagent reservoir areas 67 band 67 c in two places further on an upstream side than the analysisarea 63 b (refer to FIG. 15B). In this case, it is possible to store onekind of reagent R1 (for example, a primer or the like) in the reagentreservoir area 67 b in an upstream side (main flow channel 65 b side)and to store another one kind of reagent R2 (for example, an enzyme orthe like) in the reagent reservoir area 67 c in an downstream side(analysis area 63 b side) (refer to FIG. 15B).

As described above, it is possible to prevent the mixing of the reagentsuntil when a liquid is introduced in the microchip by storing reagentsnecessary for reaction in analysis areas 63 a and 63 b or in reagentreservoir areas 67 a to 67 c in advance. For this reason, it is possibleto suppress nonspecific reaction (primer dimer, oligomer or the like) inthe analysis areas. It is considered that the effect of suppressing thenonspecific reaction can be more enhanced from having the flow channelstructure in which the microchip according to the sixth embodiment cansupply the liquid to each of the analysis areas from the inlet part atthe same time.

In addition, in the microchip according to the sixth embodiment, it issuitable to store reagents in the analysis areas 63 a and 63 b or inreagent reservoir areas 67 a to 67 c using a technique of dripping eachliquid containing each reagent into the areas and of drying the drippedliquid for solidification. The solidification of the different reagentsin different places does not cause any mixing of the reagents, therebysuppressing any nonspecific reaction.

In a case where each solution containing each reagent is dripped in thereagent reservoir areas 67 a to 67 c and is dried for thesolidification, the each solution dripped into the reagent reservoirareas 67 a to 67 c has to be treated not to flow into flow channels (65a, 66 a, 65 b, and 66 b). An example of the method includes controllingof surface properties. It is considered that it is possible to preventthe solution from flowing into the flow channels when dripping eachsolution containing each reagent into the reagent reservoir areas 67 ato 67 c by providing the inside of the flow channels withhydrophobicity, for example. From this point of view, it is suitable touse plastic, polydimethylsiloxane, or the like that exhibitshydrophobicity as a material of the substrate constituting themicrochip.

In a case of using a material of which the surface exhibitshydrophilicity as a material of the substrate constituting themicrochips 61A and 61B, it is preferable to perform a hydrophobictreatment. Examples of the hydrophobic treatment of an inorganicmaterial such as glass include silane coupling, fluorine coating, or thelike.

In addition, in a case of storing respective reagents solidified byfreeze-drying or the like in the reagent reservoir areas 67 a to 67 c,it is desirable that the size of the solidified reagent be smaller thanthe diameter of the reagent reservoir areas 67 a to 67 c. In a case ofusing the freeze-drying method, the size of the solidified reagentsdepends on the size of the reagents when frozen. For this reason, it isdesirable that the diameter of a vessel when a reagent is frozen besmaller than the diameter of the reagent reservoir areas 67 a to 67 c.Even in a case of compressing and solidifying a reagent, which ispowdered by granulating, by tableting, it is desirable that the diameterof the solidified reagent be smaller than the diameter of the reagentreservoir areas 67 a to 67 c.

In a case where the reagent reservoir areas 67 a to 67 c are located inan upstream side of the analysis areas 63 a and 63 b, it is consideredthat the solubility is improved by the flow of the liquid generatedwhile supplying the liquid to the reagent reservoir areas 67 a to 67 c.In addition, it is considered that the reagent is uniformly mixed by thedissolved reagent which is flowed into the analysis areas 63 a and 63 b.

In a case where the capacity of the analysis areas 63 a and 63 b islarge, there is a case where the concentration of the reagent is notuniformly distributed because the reagent is hardly dispersed even ifthe reagent is dissolved in the analysis areas 63 a and 63 b. However,it is considered that the concentration of the reagent becomes uniformby the reagent solution, which was dissolved in the reagent reservoirareas 67 a to 67 c in advance, flowed into the analysis areas 63 a and63 b.

In addition, in the sixth embodiment, it is possible to configure themicrochip as the following.

That is, a plurality of reagent reservoir areas are installed in anupstream side of the analysis area and numbers are given to the reagentreservoir areas starting from the upstream side. Once it is determinedas to which reagent is to be put in what reagent reservoir area havingwhat number, it is possible to confirm as to which reagent is enclosedin what reagent storage location. The same principle also applied toconfirmation of the reagent while manufacturing the microchip.

For example, in a case of a microchip having a configuration providedwith five reagent reservoir areas in an upstream side of each ofanalysis areas, a reagent containing an enzyme, which is commonly usedfor every reaction, is enclosed in each of the analysis areas, and areagent containing a primer for successively detecting A to E isenclosed in the first to fifth reagent reservoir areas. Whenmanufacturing a microchip in such a manner, it is possible toautomatically recognize the reagent using an image or the like, and thesame principle also applies to prevention of an input error during themanufacturing.

Combination of Embodiments

In the embodiments of the present technology, it is possible toconfigure a microchip according to embodiments of the present technologyby appropriately combining a configuration described in each embodimentwith a configuration described in other embodiments within the scope notimpairing the purpose of the embodiments of the present technology. Forexample, parts of the branch flow channels in the microchips of thefirst, third, and fourth embodiments may be set as branch flow channelsprovided with the constriction part or the resistance part described inthe fifth embodiment. In addition, for example, the second flow channelor the display area described in the fourth embodiment may be installedin parts or all of the analysis areas of the microchips of the secondand the third embodiments. Furthermore, for example, a part of the mainflow channel in the plurality of main flow channels in the microchip ofthe third embodiment may be formed in a way such that the lengths, thewidths, and the depths of the flow channels from the inlet part to theplurality of analysis areas connected to the part of the main flowchannel are substantially the same as each other, as described in thesecond embodiment.

In addition, the above-described embodiments exemplified a configurationincluding a inlet part, but the number of inlet parts in the microchipmay be two or more. In this case, regarding a plurality of analysisareas connected to an inlet part through a flow channel, a liquid issupplied to the plurality of analysis areas connected to an inlet part,from the inlet part at the same time.

Method of Manufacturing Microchip

The microchip according to an embodiment of the present technology asdescribed in each of the above-described embodiments is manufactured byforming a flow channel that supplies a liquid to a plurality of analysisareas from an inlet part at the same time in a substrate. In this case,it is suitable to perform the forming of the flow channel in thesubstrate once the flow channel is designed in consideration ofresistance elements based on the flow channel such as the length, thewidth, and the depth of the flow channel. As described in thedescription of the substrate of the first embodiment, the method offorming the flow channel in the substrate can be performed using, forexample, a technique such as etching, nanoimprinting, injection molding,cutting, or the like.

An embodiment of the present technology can have configurations as thefollowing.

(1) A microchip including: an inlet part to which a liquid is injected;a plurality of analysis areas to which the liquid is supplied from theinlet part; and a flow channel which is formed to supply the liquid tothe plurality of analysis areas at the same time.

(2) The microchip according to above-described (1), in which the flowchannel is formed in a way such that flow channel resistances from theinlet part to each of the analysis areas are substantially the same aseach other.

(3) The microchip according to above-described (1) or (2), in which theflow channel includes a main flow channel connected to the inlet partand a plurality of branch flow channels which are branched from the mainflow channel and are connected to each of the analysis areas.

(4) The microchip according to above-described (3), in which across-sectional area perpendicular to the flow direction of the liquidin the main flow channel is larger than a total cross-sectional areaperpendicular to the flow direction of the liquid in the plurality ofbranch flow channels.

(5) The microchip according to above-described (3) or (4), in which, inthe plurality of analysis areas, the flow channel is formed in a waysuch that a flow channel resistance of a first branch flow channel whichis connected to a first analysis area positioned closest to the inletpart and a flow channel resistance from a connection point of the firstbranch flow channel in the main flow channel to analysis areas exceptfor the first analysis area are substantially the same as each other.

(6) The microchip according to any one of above-described (3) to (5),further including: a plurality of the main flow channels, in which themain flow channels are formed in a way such that flow channelresistances of each of the main flow channels from the inlet part toanalysis areas positioned closest to the inlet part are substantiallythe same as each other.

(7) The microchip according to any one of above-described (1) to (6),further including: a second flow channel through which the liquid flowsout from the analysis areas; and a display area which is connected toeach of the analysis areas through the second flow channel and presentssupplying status of a liquid to each of the analysis areas.

(8) The microchip according to above-described (7), in which the secondflow channel includes a plurality of second branch flow channelsconnected to each of the analysis areas and a second main flow channelconnected to the plurality of second branch flow channels.

(9) The microchip according to above-described (7) or (8), in which thesecond main flow channel is formed in a way such that the width and/orthe depth of a cross-section perpendicular to the flow direction of theliquid in the second main flow channel increase gradually or in astepwise manner toward the display area.

(10) The microchip according to any one of above-described (7) to (9),in which a storage part for preventing backflow of the liquid isprovided in a predetermined position of the second flow channel.

(11) The microchip according to any one of above-described (1) to (10),in which a reagent reservoir area is provided separately from theanalysis areas between the inlet part and the analysis areas.

(12) The microchip according to any one of above-described (1) to (11),in which the flow channel is formed in a way such that the flow channelresistances from the inlet part to each of the analysis areas aresubstantially the same as each other and the flow channel resistance isderived from resistance elements such as the viscosity of the liquid,the length of the flow channel, and the size of a cross-sectionperpendicular to the flow direction of the liquid in the flow channel.

(13) The microchip according to above-described (12), in which thecross-section perpendicular to the flow direction of the liquid in theflow channel has a rectangular shape, and the flow channel resistance inthe flow channel is calculated by the following Formula (I).

$\begin{matrix}{R = {\frac{12\eta \; L}{1 - {0.63( {h\text{/}w} )}} \cdot \frac{1}{h^{3}w}}} & (I)\end{matrix}$

(In Formula (I) described above, R represents the flow channelresistance [Pa·s/mm³] of the flow channel, η represents the dynamicviscosity [Pa·s] of the liquid, L represents the length [mm] of the flowchannel, h represents the depth [mm] of the flow channel, and wrepresents the width [mm] of the flow channel.)

(14) The microchip according to any one of above-described (3) to (6),further including: a constriction part in the branch flow channel, inwhich the constriction part is formed in a way such that flow channelresistances from the inlet part to each of the analysis areas aresubstantially the same as each other.

(15) The microchip according to any one of above-described (3) to (6),further including: a resistant part against flow of the liquid isprovided in the branch flow channel, in which the resistant part isformed in a way such that flow channel resistances from the inlet partto each of the analysis areas are substantially the same as each other.

(16) A method of manufacturing a microchip including: forming a flowchannel, through which a liquid can be supplied to a plurality ofanalysis areas from an inlet part to which the liquid is injected at thesame time, in a substrate.

Example

The effect of the microchip according to an embodiment of the presenttechnology is described in detail using an example as follows.

In the example, a substrate having a three-layered structure of glasscover-pdms-glass cover in which in inlet (inlet part), a plurality ofwells (analysis areas), and a flow channel pattern are formed on asubstrate layer made of polydimethylsiloxane (PDMS) using a glass coveras a support is used. The formation of the inlet, the wells, and theflow channel pattern on the substrate layer is implemented bymanufacturing SU-8 mold formed with the flow channel pattern or the likeusing photolithography and by forming PDMS using the mold (template).Accordingly, a substrate layer made of PDMS on which the flow channelpattern or the like is transferred is obtained.

A top view schematically illustrating the thus manufactured microchip 71is shown in FIG. 16.

The microchip 71 is provided with an inlet 72 to which a sample solution(liquid) is injected, five wells 73 (731, 732, 733, 734, and 735), and aflow channel 74 connected from the inlet 72 to the wells 73. Moreover,the flow channel 74 has a main flow channel 75 and five branch flowchannels 76 (761, 762, 763, 764, and 765) connected to each of the wells73 branched from the main flow channel 75.

When manufacturing the microchip 71, the lengths of the main flowchannel 75 and the branch flow channels 76 and the size (widths anddepth) of the shape of the vertical cross-section are set as Table in away such that the flow channel resistances from the inlet 72 to each ofthe wells 73 are substantially the same as each other. The flow channelresistances are calculated by Formula (I) described in the firstembodiment. In addition, since the main flow channel 75 from the inlet72 to the well 731 positioned closest to the inlet 72 is common withrespect to each of the analysis areas, the size of the common part ofthe main flow channel 75 is omitted in Table.

TABLE First well 731 Second well 732 Third well 733 Fourth well 734Fifth well 735 Main flow 0 5 10 15 20 channel length (mm) Main flow 0.20.2 0.2 0.2 0.2 channel width (mm) Main flow 0.1 0.1 0.1 0.1 0.1 channeldepth (mm) Main flow 0 986409 1972818 2959227 3945636 channel resistance(Pa · s/mm³) Branch flow 2 2 2 2 2 channel length (mm) Branch flow 0.10.1 0.1 0.1 0.1 channel width (mm) Branch flow 0.03 0.031 0.0323 0.03370.0353 channel depth (mm) Branch flow 0.003 0.0031 0.00323 0.003370.00353 channel cross- sectional area (mm²) Branch flow 1096040610011339 8941542 7960974 7016577 channel resistance (Pa · s/mm³) Totalflow 10960406 10997748 10914360 10920201 10962213 channel resistance (Pa· s/mm³)

100 μM of Cy3-DNA solution (sequence: [Cy3]CGCGATGTGGGAAAGATTCT) wasvacuum-injected to the inlet 72 of the microchip 71 as a samplesolution. Then, the situation of the injection of the sample solution toeach of the wells 73 was photographed at 8.8 shot/second and an averagevalue of the fluorescence intensity in each well is plotted with respectto the time by analyzing the photographed connection image file usingimage analysis software. The result is shown in FIG. 17A together withthe image suitable for indicating the timing of supplying the samplesolution to each of the wells 73.

The result of a comparative example performed similarly to theabove-described experiment is also shown in FIG. 17B. In the comparativeexample, the position, the size, and the like of the inlet and the wellsare the same as those in the example, but a microchip which is notformed in a way such that the flow channel resistances from the inlet toeach of the wells are substantially the same as each other was used.

As shown in FIG. 17B, it was found that the sample solution was suppliedto a well starting from a well which is positioned closest to the inletin the microchip of the comparative example. Moreover, when the fillingof a well positioned closest to the inlet with the sample solution isfinished, the filling amount of the wells in a third row to a fifth rowwas less than 50%. In addition, it was confirmed that there is afluctuation in the fluorescence intensity in each of the wells.

On the contrary, as shown in FIG. 17A, it was confirmed that the samplesolution was supplied to each of the wells 73 almost at the same time inthe microchip 71 of the example. In addition, it was confirmed that thefluorescent intensities in the wells 73 also tend to be coincident.Thus, according to the microchip 71 of the example, it is possible toreduce the fluctuation of the reaction in the wells 73 due to thedeviation in completion time of filling of the wells 73 with the samplesolution.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A microchip comprising: an inlet part to which aliquid is injected; a plurality of analysis areas to which the liquid issupplied from the inlet part; and a flow channel which is formed tosupply the liquid to the plurality of analysis areas at the same time.2. The microchip according to claim 1, wherein the flow channel isformed in a way such that flow channel resistances from the inlet partto each of the analysis areas are substantially the same as each other.3. The microchip according to claim 2, wherein the flow channel includesa main flow channel connected to the inlet part, and a plurality ofbranch flow channels which are branched from the main flow channel andare connected to each of the analysis areas.
 4. The microchip accordingto claim 3, wherein a cross-sectional area perpendicular to the flowdirection of the liquid in the main flow channel is larger than a totalcross-sectional area perpendicular to the flow direction of the liquidin the plurality of branch flow channels.
 5. The microchip according toclaim 4, wherein, in the plurality of analysis areas, the flow channelis formed in a way such that a flow channel resistance of a first branchflow channel which is connected to a first analysis area positionedclosest to the inlet part and a flow channel resistance from aconnection point of the first branch flow channel in the main flowchannel to analysis areas except for the first analysis area aresubstantially the same as each other.
 6. The microchip according toclaim 5, further comprising: a plurality of the main flow channels,wherein the main flow channels are formed in a way such that flowchannel resistances of each of the main flow channels from the inletpart to analysis areas positioned closest to the inlet part aresubstantially the same as each other.
 7. The microchip according toclaim 6, further comprising: a second flow channel through which theliquid flows out from the analysis areas; and a display area which isconnected to each of the analysis areas through the second flow channeland presents supplying status of a liquid to each of the analysis areas.8. The microchip according to claim 7, wherein the second flow channelincludes a plurality of second branch flow channels connected to each ofthe analysis areas and a second main flow channel connected to theplurality of second branch flow channels.
 9. The microchip according toclaim 8, wherein the second main flow channel is formed in a way suchthat the width and/or the depth of a cross-section perpendicular to theflow direction of the liquid in the second main flow channel increasegradually or in a stepwise manner toward the display area.
 10. Themicrochip according to claim 9, wherein a storage part for preventingbackflow of the liquid is provided in a predetermined position of thesecond flow channel.
 11. The microchip according to claim 1, wherein areagent reservoir area is provided separately from the analysis areasbetween the inlet part and the analysis areas.
 12. The microchipaccording to claim 2, wherein the flow channel resistance is derivedfrom resistance elements such as the viscosity of the liquid, the lengthof the flow channel, and the size of a cross-section perpendicular tothe flow direction of the liquid in the flow channel.
 13. The microchipaccording to claim 12, wherein the cross-section perpendicular to theflow direction of the liquid in the flow channel has a rectangularshape, and wherein the flow channel resistance in the flow channel iscalculated by the following Formula (I). $\begin{matrix}{R = {\frac{12\eta \; L}{1 - {0.63( {h\text{/}w} )}} \cdot \frac{1}{h^{3}w}}} & (I)\end{matrix}$ in Formula (I) described above, R represents the flowchannel resistance [Pa·s/mm³] of the flow channel, η represents thedynamic viscosity [Pa·s] of the liquid, L represents the length [mm] ofthe flow channel, h represents the depth [mm] of the flow channel, and wrepresents the width [mm] of the flow channel.
 14. The microchipaccording to claim 3, further comprising: a constriction part in thebranch flow channel, wherein the constriction part is formed in a waysuch that the flow channel resistances from the inlet part to each ofthe analysis areas are substantially the same as each other.
 15. Themicrochip according to claim 3, further comprising: a resistant partagainst flow of the liquid is provided in the branch flow channel,wherein the resistant part is formed in a way such that the flow channelresistances from the inlet part to each of the analysis areas aresubstantially the same as each other.
 16. A method of manufacturing amicrochip comprising: forming a flow channel, through which a liquid canbe supplied to a plurality of analysis areas from an inlet part to whichthe liquid is injected at the same time, in a substrate.